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International Journal on Algae

ISSN for PRINT: 1521-9429

Institutional price:	$905.00
Issues per year:	4

Best Paper Award Selection - Editorial Board Site

2001, Volume3

130 pages

Issue price - $216.00

Transformation of urea during the growth of some blue-green (Cyanoprocaryota) and green (Chlorophyta, Chlorococcales) algae

P. D. Klochenko
Institute of Hydrobiology, National Academy of Sciences of Ukraine, 12, Geroyev Stalingrada Pr., 04210 Kiev, Ukraine

V. A. Medved'
Institute of Hydrobiology, National Academy of Sciences of Ukraine, 12, Geroyev Stalingrada Pr., 04210 Kiev, Ukraine

P. M. Tsarenko
N.G. Kholodny Institute of Botany, National Academy of Sciences of Ukraine, 2, Tereshchenkavskaya St., 01001 Kiev, Ukraine

Ye. V. Borisova
N.G. Kholodny Institute of Botany, National Academy of Sciences of Ukraine, 2, Tereshchenkovskaya St., 01001 Kiev, Ukraine

Z. N. Gorbunova
Institute of Hydrobiology, National Academy of Sciences of Ukraine, 12, Geroyev Stalingrada Pr., 04210 Kiev, Ukraine

ABSTRACT

The accumulation of ammonium nitrogen in the culture medium of green and blue-green algae of the genera The accumulation of ammonium nitrogen in the culture medium of green and blue-green algae of the genera Acutodesmus (Hedew.) Tsar. (1 species), Chlorella Beijer, (1), Coelastrum Nag. (1), and Desmodesmus (Chod.) An, Friedl et Hegew. (5) was studied in the process of their growth on urea. It has been revealed that a sharp increase in the NH₄⁺ concentration in the culture of blue-green algae due to the high activity of urease leads to their inhibition, and eventually to their death. Chlorococcal algae containing urea amidase differed in a low intensity of urea hydrolysis and in the absence of the inhibitory effect of NH₄⁺ ions on their growth. In addition, it has been shown that the character of urea decomposition depends on the biological peculiarities of the species, which is the most distinct in representatives of the order Chlorococcales. The presence of accompanying (associated) bacteria in their culture leads to a decrease in the ammonium nitrogen quantity in the medium.